40005631 has 4 divisors (see below), whose sum is σ = 40097200. Its totient is φ = 39914064.

The previous prime is 40005611. The next prime is 40005643. The reversal of 40005631 is 13650004.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 40005631 - 2²³ = 31617023 is a prime.

It is a super-2 number, since 2×40005631² = 3200901023416322, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40005599 and 40005608.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40005611) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45126 + ... + 46003.

It is an arithmetic number, because the mean of its divisors is an integer number (10024300).

Almost surely, 2^40005631 is an apocalyptic number.

40005631 is a deficient number, since it is larger than the sum of its proper divisors (91569).

40005631 is an equidigital number, since it uses as much as digits as its factorization.

40005631 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91568.

The product of its (nonzero) digits is 360, while the sum is 19.

The square root of 40005631 is about 6325.0004743083. Note that the first 3 decimals coincide. The cubic root of 40005631 is about 342.0112367066.

Adding to 40005631 its reverse (13650004), we get a palindrome (53655635).

The spelling of 40005631 in words is "forty million, five thousand, six hundred thirty-one".